Engine-driven centrifugal pump



neath the chamber.

Patented Sept. 28, 1943 ENGINE-DRIVEN CENTRIFUGAL PUMP Leonard PelhamLee, Lawrence Hathaway, and Arthur Sawbridge, Coventry, England,assignors to Coventry Climax Engines Limited, Coventry, Warwickshire,England Application December 1, 1941, Serial No. 421,218 In GreatBritain September 29, 1941' 6 Claims. (Cl. 103113) This inventionrelates to a centrifugal pump for lifting and delivering liquids, suchas is driven by an' internal-combustion engine, of the kind any liquidthat may be drawn in from the inlet side of the pump and to prevent itfrom passing to the ejector.

According to the present invention, the said means is disposed in thecasing of the pump, thus reducing the number of pipe unions andsimplifying the arrangement. Preferably the pump has a closed chamberformed in the upper part of its casing and providing the water trap, thechamber having a standpipe therein whichcommunicates at its lower endwith an opening leading to the inlet side of the pump, whilst the upperpart of the chamber has an opening connected to the ejector. The chamberis preferably on that side of the pump casing remote from the engine,the pump inlet being on the same side and be- The inlet and outletopenings for the chamber may be arranged to be ccaxial, in which casethe upper end of the stand pipe is offset or otherwise arranged so as toprevent any water which may be drawn in from passing directly upto theoutlet opening. The water trapped in the chamber can leak back to theinlet side of the pump when priming is completed from holes providednear the bottom of the standpipe.

The invention further consists in mounting a valve unit, for controllingthe connection of the inlet side of the pump to the ejector, directlyupon the pump casing. Furthermore, the valve unit is preferably adaptedalso to control the supply to the engine, for cooling purposes, of partof the water being pumped.

In the accompanying sheet of drawings:

Figure 1 is a perspective view of a pumping unit adapted according tothe invention;

Figure 2 is a vertical section, through the axis of the pump, of theupperfportion of the pump; and

Figure 3 is a vertical section through the axis of the rotary member ofthe valve unit, this section being at right-angles to the section ofFigure 2.

In the drawing there is a casing l I over the pumping unit, the casingbeing shown broken away to disclose the outline of aninternal-combustion engine I2 the crankshaft of which is mechanicallyconnected to thevrotor of the pump l3. The latter is of the single-stagerotary-vane type. The volute chamber 14 is provided with two outlets l5,l5 on one side, and I6 represents the pump inlet, this being coaxialwith the rotor. ll represents the rotor chamber, the rotor being omittedfor the sake of simplicity. Theinlet I6 extends through an opening H3 inthe casing II.

In the present instance the casing or bodyof the pump I3 has a hollowchamber I9 formed in it during casting, this chamber being closed by acover plate 20. Mounted in the chamber I9 is a standpipe 2| the upperend of which is blocked, as shown at 22, while lateral openings 23 areprovided beneath.- Lateral openings 24 are also provided at the base ofthe standpipe. The lower end of the latter communicates by a passage 25with a peripheral groove 26 in a spacing annulus 21, the latterreceiving the adjacent end of The peripheral groove 26 the pump inletl6. communicates by a number of radial holes, of which only one (28)appears in the illustration, with a peripheral groove 29 around theinner end of the inlet pipe, and the latter groove communicate's withthe bore 30 of the inlet pipe through a number of radial holes-of whichonly one (3 I) appears in the illustration. The top of the chamber l9communicates by a passage 32 with an opening in a machined face 33provided at the top of the pump body. Beside the upper end of thispassage 32 is the upper end of a second pas sage 34 leading to theoutlet side of the pumpi. e., to the volute chamber I4.

Mounted upon' the machined face 33 is the body 35 of a valve unit havingpassages 36 and 3'! to communicate with the passages 32 and 34respectively. The passages in the body of the valve unit are intersectedby a tapered bore in which is mounted a rotary valve element 38. Thereare in the latter two through bores 39, 39

at right-angles to one another, so'that in one position (as shown inFigure 3) the passage 36 will be blocked and the passage 37 open, whileif the rotary element 38 be turned through 90 the passage 31 will beblocked and the passage 36 open. The rotary element 38 is operable by anactuating lever 40 which passes through a slot (not shown) in the casingH.

4| represents the exhaust manifold of the engine and 42 anexhaust-operated .ejector of a kind known per se. The manifold 4| isconnected with a drum 43 to the upper end of which is attached the mainexhaust pipe 44. In the drum is a clapper valve 45 the actuating spindleof which carries an arm 45 linked at 41 with a crank arm 48 fast on theactuating lever 40. The exhaust manifold also communicates with theejector. When the actuating lever 40 is pulled downwardly (Figure 1) toclose the clapper valve 45 on the inlet to the main exhaust pipe 44, theexhaust gases are diverted to pass through the tube 49 into the deliverypipe This creates a depression in the annular space 52 around the tube49. The space 52 is connected to the pipe 53 which leads, it will beobserved from Figure 3, to the passage 36.

54 represents a tank containing cooling water, the tank being connectedwith the engine jacket in a known manner. Only one of the connectionpipes 55 appears in the illustration. Disposed in the interior of thetank, for cooling the water therein, is a length of coiled copper tubing56 one end.,5'l of which extends to the outside of the tank for exhaustpurposes, while the other end is connected by a pipe 58 which, it willbe observed from Figure 3, communicates with the passage 31.

The operation of the unit is as follows. After starting up the engine,in order to prime the pump the actuating lever 40 is pulled downwardly,thereby closing the clapper valve 45 and turning the rotary element 38through 90 from the position shown in Figure 3. In these conditions nowater is being delivered through the copper tubing 56, but there is asufilcient quantity of water in the tank 54 and engine jacket to ensurethat the engine will not become overheated during the period thatpriming is being effected.

On the other hand, the passage 36 is open, and the inlet side of thepump is thus placed in communication with the ejector through the pipe53. As will be readily understood, the action of the ejector in theseconditions is to create a depression at the inlet side of the pump, thusfacilitating the priming of the latter. If before the pump is primedwater should be drawn along the passage 25:, it will be trapped in thechamber l9, whereby such water is prevented from passing through to theejector.

When priming is completed, aswill be evidenced by delivery of water fromthe pump, the actuating lever 40 is raised through 90, thereby movingthe clapper valve away from the inlet of the main exhaust pipe, so thatthe exhaust gases can then travel to the silencer in the normal manner.At the same time the rotary element 38 is turned to the position shownby Figure 3, in which the pump inlet I6 is disconnected from the ejectorby the closing of the passage 36. The passage 31, however, is open,thereby enabling a portion of the water being pumped to be deliveredalong the passage 34 to the pipe 58, and this water, being circulatedthrough the copper-tubing 56, will serve for preventing the water in theengine jacket and tank 54 from rising to too high a temperature whilethe engine is operating the pump for normal delivery. Any water that mayhave entered the chamber l9 can then drain back to the inlet side of thepump.

What we claim as our invention and desire secure by Letters Patent ofthe United' States is:

1. In combination, a centrifugal pump of the single-stage rotary-vanetype, an internal-combustion engine connected to drive said pump,

the engine having a cooling system supplied with cooling water from theoutlet side of said pump, a valve controlling the supply of such coolingwater, an ejector operated by the engine exhaust connected to the inletside of said pump for creating a subatmospheric pressure forfacilitating the priming of said pump, and a valve in the connection ofsaid inlet side to said ejector, said two valves being combined in aunit having a single actuating means whereby when one valve is closedthe other valve is open and vice versa, and said valve unit beingmounted directly upon the casing of said pump.

'2. In combination, a centrifugal pump of the single-stage rotary-vanetyp an internal-combustion engine connected to drive said pump, anejector operated by the engine exhaust connected to the inlet side ofsaid pump for creating a sub-atmospheric pressure for facilitating thepriming of said pump, a valve in the connection between said inlet sideand said ejector, said valve being mounted directly upon the casing ofsaid p unp, and a water trap disposed in said casing and connectedbetween said valve and said inlet side.

3. In combination, a centrifugal pump of the single-stage rotary-vanetype, an internal-combustion engine connected to drive said pump, theengine having a cooling system, adapted to be supplied with coolingwater from said pump, a valve controlling the supply of such coolingWater, an ejector operated by the engine exhaust connected to the inletside of said pump for creating a sub-atmospheric pressure forfacilitating the priming of said pump, a valve controlling theconnection of said inlet side to said ejector, said two valves beingcombined in a unit having a single actuating means whereby when onevalve is closed the other valve is open and vice versa, said valve unitbeing mounted directly upon the casing of said pump, and a water trapdisposed in said casing to prevent water from passing to said ejector,said water trap being connected to said inlet side and to said valveunit.

4. In combination, a centrifugal pump of the single-stage rotary-vanetype, an internal-combustion engine connected to drive said pump, theengine having a cooling system adapted to be supplied with cooling waterfrom said pump, a valve controlling the supply of such cooling water, anejector operated by the engine exhaust connected to the inlet side ofsaid pump for creating a sub-atmospheric pressure for facilitating thepriming of the pump, a valve controlling the connection of said inletside to said ejector, said two valves being combined in a unit having a.single actuating means whereby when one valve is closed the other valveis open and vice versa, said valve unit being mounted directly upon thetop of the casing of said pump, and a closed chamber formed in saidcasing below said valve unit, said chamber having a standpipe thereincommunicating with said inlet side and said chamber having an outletopening leading to said second-mentioned valve.

5. In combination, a centrifugal pump of the single-stage rotary-vanetype, an internal combustion engine connected to drive said pump, anejector operated by the engine exhaust connected to the inlet side ofsaid pump for creating a sub-atmospheric pressure for facilitating thepriming of said pump, a closed chamber formed in the upper part of thepump casing adapted to trap any liquid that may be drawn in from theinlet side of said pump. and prevent its passage to said ejector,a'standpipe in said chamber communicating at its lower end with anopening leading to the inlet side of said pump, th'e'upper pa rt of saidchamber having an opening connected. to said ejector,- said pump inletand'said chamber beingpositioned on the remote side of said engine.

'8. In combination, a centrifugal pump of the single-stage rotary-vanetype, an internal combustion engine connected to drive said pump, anejector operated by the engine exhaust connected to the inlet side ofsaid pump for creating a sub-atmospheric pressure for facilitating thepriming of said pump, a closed chamber formed in the upper part of thepump casing adapted to trap any liquid that may be drawn in from theinlet side of said pump and prevent its passage to said ejector, astandpipe in said chamber communicating at its lower endwith an openingleading to the inlet side of said pump,

the upper part of said chamber having an opening connected to saidejector, said pump inlet and said chamber being positioned on the remoteside of said engine, said inlet and outlet openings for said chamberbeing coaxial, the upper I

